class_docstr: Constrain to lower-triangular square matrices with all ones diagonals.
code: def check(self, value):
      value_tril = value.tril()
      lower_triangular = (
          (value_tril == value)
          .view(value.shape[:-2] + (-1,))
          .min(-1)[0]
      )
  
      ones_diagonal = (value.diagonal(dim1=-2, dim2=-1) == 1).min(-1)[0]
      return lower_triangular & ones_diagonal
  
imports: from torch.distributions.constraints import *
  import torch
  from torch.distributions.constraints import Constraint, independent, lower_cholesky, positive, positive_definite
  from torch.distributions.constraints import __all__
label_desc: Use image node_id 1 for calling the _UnitLowerCholesky obj's underlying member method code with example usage: obj.check(value) and returns: unknown